Liquid thermoelectric converter composed of organic electrolyte with reduced solution resistance

Abstract

The maximum power (W_max) of liquid thermoelectric converter (LTE) is determined by the electrochemical Seebeck coefficient α and device resistance R as W_max = α²ΔT²/4R, where ΔT is the temperature difference between the electrodes. In organic LTE containing Fe²⁺/Fe³⁺, α is much higher than that of the corresponding aqueous LTE even though R is higher. Here, we searched for pure and/or mixed solutions electrolyte with smaller solution resistance R_s using viscosity η as a clue. We demonstrated that W_max of LTE (electrode distance d is 10 mm) using acetone-H₂O electrolyte is 31 % higher than W_max of the corresponding aqueous LTE.